1. Field of the Invention
The present disclosure relates to imaging, and more particularly to lag correction in image data generated by imaging devices.
2. Description of Related Art
Imaging devices commonly employ a sensor to acquire image data from light incident on the sensor. The sensor typically converts light incident on the sensor into a photocurrent and integrates that photocurrent over an exposure period to generate a signal, which is then communicated to a digital readout circuit. Image lag or persistence is a phenomenon demonstrated by some imaging pixel readout circuits wherein the signal voltage integrated for one exposure period contains a residual voltage imparted from signal in a previous exposure period.
Image lag or persistence can result under several different circumstances. For example, an incomplete reset of the pixel or integration node prior to the subsequent integration period can cause imaging lag or persistence. Imaging lag or persistence can also result from bandwidth constraints in the signal path from the pixel, such as between the pixel and the readout circuit or between the readout circuit and downstream devices. Lag behavior of a pixel readout circuit may be measured or modelled, but digital correction has historically been prohibitive at the digital readout circuit due to the physical constraints of the silicon area of the readout circuit.
Such conventional methods and systems have generally been considered satisfactory for their intended purpose. However, there is still a need in the art for improved imaging systems and methods. The present disclosure provides a solution for this need.